1600 MADISON ST 2016-01-01 MF Import

� � Mr. Chris Lark Febniary 20, 2001 Based on the measured standard penetration resistance values, the on-site soils are sufficiently � dense tha[ the polential for earthquake induced soil liquefaction is considered to be vcry low. [n addition, based on existing information, the site is not underlain by any known active fault. Therefore, ground rupture from faulting and liquefaction are not design consiclerations for this � project. p 5.2 FOOTINCS � Conventional spread footings bearing direcUy on the underlying glacial till or a structural fill extending to the till are recommended for lhe suppoR of the new fire stalion. The footings �_ should be designed based on a maximum allowable bearing pressure of 3,000 psf that may be increased by 1/3 for transient conditions such as wind and seismic loadings. All exterior footings u shouid be iounded a minimum dislance of 18 ir,ches Uelow the adjacent finished grade, and all t interior footings should be at least 12 inches below the top of floor slab. 1_ � Lateral forces resulting from wind or seismic events may be resisted by a combination of sliding resistance a[ the footing base and passive earth pressurc against the buried portions of the structure. A coefficient of friction of 0.5 may be assumed between dre Uase of the footings and the bearing surface. Passive soil resistance against lhe sides of buried foolings can be estimated using an equivalent (luid unit weight of 500 pounds per cubic foot (pcQ assuming that the Uackfill against tlte foo!ings consists of granular structural fill compacted to 95 percent of the maleriaPs maximum dry density, detem�incd using ASTM D1557 (Modified proctor). The recommended passive resistance includes a factor of safety of about 1.5. All footing excavations should be trimmed neat and the bottom of q�e excavation should be cazefully prepazed. The footing excavations should be observed by an engineer from our firm � prior to placing steel and concrete, to verify that dte recommendations of this report have been followed, and that an appropriate bearing slratum has been exposed. Tot :i and differential settlements of footings designed and constructed in accordance with our recommendations are � anticipated to be within tolerable limits. Under static loading, we estimate that the spread footings may experience total settlemenls of less than about %Z inch. Differential settlements between two adjacent load-bearing components supported on competent soils are expected to be . less than about Y< inch. � 5.3 CONCRETC SLA[3-ON-GRADE Interior slab-on-grade floors should be provided with an adequate moisture breal:. The capillary � break should consist of a minimum of 6 inches of &ee-draining, crushed rock or �vell-graded sand and gravel wliich is compacted to a firni and unyielding condition. We recommend that the �capillnry break material have a maximum partide size of'/a inch, with no more than 80 percent , passing the No. 4 sieve and less than 5 pement passing the U.S. Stanclard No. 100 sieve. In areas 00-04G-100 Geotcch Report 4 PanGEO, Inc. ��